Author Topic: soldering fume extractor?  (Read 3576 times)

Offline PekkaNF

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soldering fume extractor?
« on: March 14, 2016, 01:21:38 PM »
Professional ones are expensive to buy and filters are pretty expensive too.

My understanding is that lead free solders are more harmful to work with than leaded. I'm not using leadfree stuff.

This far I have used very little external ventilation. I have used small bathroom fan that blows all out. That tends to use some energy in winter and it is not that efficient. No smells leave the room, but smoke lingers when soldering.


Most of the hobby stuff seems to be this caliber:
http://www.reichelt.de/?ARTICLE=87379&PROVID=2773&wt_mc=amc14189045499978

I really wonder if the fan and filter is really up to task?

That sort of "computer" fan is not that powerful with a lot of back pressure.

Will those work at any rate?

I'm wondering to what extent it is possible to recyle air trough filter and how much should be exhausted out?

There is some other small gluing, lamination etc. activities that could benefit from modest fume hood / draugh cabinet type solution. Nothing like lab quality hazmat stuff. More like toy model paint hood.

There are locally available paint wall filters, and filter cloth by meters, different grades, activated charcoal material as well.

Pekka

Offline hermetic

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Re: soldering fume extractor?
« Reply #1 on: March 14, 2016, 03:38:26 PM »
Lead free solders are mostly tin/antimony, with traces of copper or silver, depending on the usage. There is very little risk of evaporating any metal with a soldering iron, most of the visible smoke is from the flux. How about something like a forge canopy or cooker hood connected to a remote centrifugal fan. I think the fumes from soldering with lead free must be inherently safer, as there is no lead present, but if you are talking about electrical or electronic soldering, you are using minimal heat to avoid component damage, and the likelihood of any metal being vapourised is extremely small.
Phil

Offline PekkaNF

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Re: soldering fume extractor?
« Reply #2 on: March 15, 2016, 01:13:39 AM »
My readin indicates that lead free solder is more dangerous to work with than lead based system:
http://www.wellerzerosmog.com/health_risk/

There are a lot same type texts and not all of them are from solder fume extractors.

Pekka

Offline chipenter

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Re: soldering fume extractor?
« Reply #3 on: March 15, 2016, 03:58:00 AM »
The filters in the link look like sponge coaterd with charcole I can't see them lasting very long , the filters for a cooker hood last for a year and are mutch larger but cost more initaly .
Jeff

Offline JerryNotts

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Re: soldering fume extractor?
« Reply #4 on: March 15, 2016, 05:05:14 AM »
Something not often apparent in discussions about lead free solders containing Antimony. Most sources where antimony is mined have arsenic intimately associated. Arsenic free antimony is inevitably more expensive. As the usual source of antimony is China where extraction is carried out in many small scale operations I would be cautious about using cheap solder!

Jerry :dremel:

Offline PekkaNF

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Re: soldering fume extractor?
« Reply #5 on: March 15, 2016, 06:32:34 AM »
All the reason to avoid lead free solder.

There are pretty good and thick activated carbon filters available and mat filters by metre.

How about a little "paint booth" type spray wall type filter, something like 500*150 mm, covered with a dust filter mat (to keep the expensive carbon filter from cloggin) then carbon mat filter right behind it, 20-50w duct fan and at fan output a vacuum cleaner HEPA-filter? Exhaust straight up?

This would not create much draft, but would filter the residue taht would othervise linger.

I should experiment with a "local" fume extraction, something like 38-60 mm flexible duct type + centrifugal fan contraption....

Pekka

Offline hermetic

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Re: soldering fume extractor?
« Reply #6 on: March 15, 2016, 06:06:00 PM »
With all due respect to Weller, whose equipment I have used for years, that link is advertising! traditional solder was a variation of amounts of lead, tin, antimony, and bismuth. this has no lead or bismuth, and they are saying it is worse? How much soldering are you going to be doing. As already said above, cooker hood filters are activated charcoal and activated charcoal, despite what the manufacturers say is pretty much all the same, and a universal filtering medium for water air, gasses, virtually everything, I do not replace the filters in my cooker hood, I just put them in the dishwasher. Put a good cooker hood over your work space, or wear a carbon filter mask if you are worried about it The other day I was in Plumbcentre, and bumped into a guy from years back who has been plumbing since he was 14, and now he's coming up for eighty and still working! and all that time or most of it using lead. Remember food is stored in cans that are coated with tin, or at least they used to be, now they use a plastic laquer and we are all suffering from low sperm count because of the bisphenol in the plastics.

Offline PekkaNF

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Re: soldering fume extractor?
« Reply #7 on: March 19, 2016, 02:20:12 PM »
I have some experinece on cooker hood filters. I have washable mesh "grease" filter and big mat charcoal filter atop of i. Works great on grase and such. Not sure if it works on smaller particles though.

I discovered trashbag method used to measure small fan flow. Basically you measure how many seconds it takes to fill an empty trash bag.

I used that on small axial duct fan. Made a setup and measured it without any filter. about 6,8 sec. Then with a big stationary vacuum cleaner exhaust filter (big yellow/orange flanges canster type. It it slowed dow the fill rate about a second, big coarse AC matt offered slightly less resitance. No problem there.

Then I checked the fan with an vacuum cleaner exhaust fileters, rating was HEPA 12, another brand new and other one rather dirty, used about a year....both of them had way too much back pressure, the fan stalled and did not fill the trash bag even on 20 seconds.... Those filters would bee good eneough, but would need completely different fan.

That's for today.

Pekka

Offline hermetic

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Re: soldering fume extractor?
« Reply #8 on: March 20, 2016, 06:07:26 AM »
I like the "trash bag" idea! Must remember that one!
Phil

Offline PK

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Re: soldering fume extractor?
« Reply #9 on: March 24, 2016, 05:41:04 AM »
Here's one I prepared earlier. There's a plenum chamber at the top and a row of holes at the back of the 'ceiling' with some filter foam over them. But mostly it just vents out the main extraction chimney (same system used for the laser cutters and reflow oven). I'm sure the roof is littered with bird carcasses by now....
The front cover slides up some PVC trim strips and can be pinned into a couple of positions. 
Before we had this, we tried all the 'point extraction' options. The only ones that removed enough fumes to prevent headaches were so noisy and cumbersome that they were impractical.
This is just some MDF, acrylic sheet and a lick of paint and removes 100% of the fumes.



Offline PekkaNF

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Re: soldering fume extractor?
« Reply #10 on: March 24, 2016, 06:42:50 AM »
That is very nice. Very professional and works100%. I would not be too worried about dead critters on the roof. Outside tends to be pretty good ventilation and any small exposure is spatially dispersed.

I have few small snags on this solution, although something like that will be my firs choice:
* I do most of my electronic hobbies in the winter and typically here weather is pretty cold. If used too long it will pump some air (heat) out.
* Snow load on the roof  cold weather. This means that the duct on the attic must be insulated and outlet must be made pretty professionally. When few tons of snow starts to move, all stuff must be bolted to roof under structure or there will be hole...
* Inavasive to the house construction.....red tape and all that.

Lot of that problem could be avoided if I could went air out trough the ventilation window, but I need to test how to avoid condensation and other issues.

My plan to is to test venting out and then build on three way valve. Exhaust out or into room. Plan "B" is a loud fan with local removal and good filtering.

Pekka

Offline PK

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Re: soldering fume extractor?
« Reply #11 on: March 24, 2016, 08:34:15 AM »
The nice thing about the fume cabinet approach is that you don't need much air flow or velocity.
All the other options require fast moving air to entrain the fumes.

Offline PekkaNF

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Re: soldering fume extractor?
« Reply #12 on: March 24, 2016, 12:51:54 PM »
Exactly.

And since you are venting it out there is no need for higher grade filter (higher presure drop or big area) and normal ducting is cheaper and very available compared to point removal system that you need high velocity, careful inlet design and flexible hose/articulated arm to get close enough.

I made rudimentary tests and point-removal system is fairly close to vacuum cleaner domain.....quiet system might be possible, but something like 400w induction motor, big radial fan, fairly big filter and it still needs silencers....doable but it really comes down to proper engineering or it olnly looks like one, but does not work properly. Nice design challenge, but if a proper radial fan does not land on my arms miracuosly, I think I'll take the easy solution.

Pekkka

Offline S. Heslop

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Re: soldering fume extractor?
« Reply #13 on: June 04, 2016, 02:27:11 PM »
Here's one I prepared earlier. There's a plenum chamber at the top and a row of holes at the back of the 'ceiling' with some filter foam over them. But mostly it just vents out the main extraction chimney (same system used for the laser cutters and reflow oven). I'm sure the roof is littered with bird carcasses by now....
The front cover slides up some PVC trim strips and can be pinned into a couple of positions. 
Before we had this, we tried all the 'point extraction' options. The only ones that removed enough fumes to prevent headaches were so noisy and cumbersome that they were impractical.
This is just some MDF, acrylic sheet and a lick of paint and removes 100% of the fumes.

That's very cool. I've been thinking about building a fume cabinet myself lately and that gives me something to go on.